Millions of miles

Tonight, in the car, Lucas started asking how many miles such and such feet are. Eventually, he got to a google feet. Driving down the interstate in rush hour traffic, I quickly calculated (excuse the rounding) 1.9 x 10^96 miles. I struggled with how to explain that value to a six year-old, even if he is a Tromble. Finally, I settled on that a trillion is a million millions, and 10^96 is a trillion, trillion, trillion, etc. trillions. He seemed good with that.